High school grading: Mastery v. handing things in

One of the students in my data-driven decision-making class (for discussion purposes, let’s call her ‘Jen’) posted this in our online discussion area:

Most grading at the high school level is more reflective of responsibility (just handing things in) and not on whether the student has truly mastered the content.

There are a lot of issues embedded in this short sentence. For example…

1. What does ‘true mastery of content’ mean (or look like) for secondary students?
2. Does high school grading really get at the idea of student responsibility?
3. If yes to #2, is ‘handing things in’ a good measure of student responsibility?
4. Does student regurgitation of low-level factual recall items on quizzes and tests constitute ‘handing things in’ or ‘mastery?’

What do you think? Do you agree with Jen’s initial statement?